ABB KD-10 Instruction Leaflet page 23

Type KD-10 and KD-11 Compensator Distance Relay
c. Connect terminals 12 to 14, 15 to 17, 16 to 18
and pass 10 amperes ac current in terminal 19
and out of terminal 13.
d. Measure the compensator voltage V
high resistance voltmeter (5,000 ohm/volt) as
tabulated below. Refer to Figure 1 (page 35) for
the location of R , R
3
Measure V
C
Between
and Fixed
Lead
End of
"L" of M R3
"L" of M
R2A
A
"L" of M
R2C
C
∆
Use sin 60° for .2 - 4.5 range
–————–—| Example 8 |———–———
For .75 - 21 ohm range T = 5.8 relay 3-phase com-
p en s a t o r w i l l r ea d V
phase-to-phase compensators where T-5.8 the volt-
ages are:
V = 120 volts (phase A)
C
V = 120 volts (phase C)
C
Accuracy of the measurement will depend on the in-
strumentation used. Factory adjusted compensator
is within ±0.5% on maximum tap and ±1% on all oth-
er taps. A realistic tolerance should be allowed for
accuracy of the primary current measurement, and
the accuracy of the voltmeter to be used to arrive at
what is a "good" compensator. A zero voltage read-
ing may be caused by open potentiometer or com-
pensator.
Additional measurements on the compensator can
be made to check the compensator tap sequence,
with a
C
AND R .
2A 2C
Voltmeter Reading
θ
 
sin
∆
V = 1.5 IT ----------------- -
 
C
sin 75°
θ
 sin 
V = 2 IT ----------------- -
 
C
sin 75°
= 9 0 .1 v o l ts a nd fo r
C
and to check on the condition of all (except terminals
8-9-circuit of the 3-phase unit) relay circuits.
With relay energized with 120 Vac only, and all
S-settings set = 1, and M = +15, check voltage drops
starting at the minimum tap and each successive "T"
tap. Voltage readings will start at the millivolt level,
and increase with successive tap values. Erratic
voltage reading will indicate open tap. These type of
readings could be taken at any relay setting except
when comparing any two relays, or readings from
the same relay at different times it should be clear
that relay settings for which measurements are tak-
en should be identical. The table below gives typical
readings for settings specified above. Use this table
as a guide only.
0.2 - 4.5 Ohms Range
T , T , T , T
A B B C
.003 - .006
.008 - .011
.017 - .021
.026 - .031
.040 - .047
.060 - .068
.75 - 21.2 Ohms Range
T , T , T , T
A B B C
.015 - .026
.032 - .054
.072 - .110
.125 - .190
.200 - .290
.295 - .470
1.3 - 36.6 Ohms Range
T , T , T , T
A B B C
.038 - .052
.080 - .100
.150 - .200
.290 - .340
.450 - .535
.700 - .860
41-490J
T
.008 - .016
.018 - .031
.004 - .063
.006 - .088
.100 - .138
.145 - .210
T
.033 - .050
.072 - .092
.145 - .190
.260 - .190
.400 - .340
.645 - .800
T
.055 - .070
.105 - .150
.220 - .300
.390 - .540
.600 - .850
.950 - 1.30
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